"I had just gone through an experience that made me write this song about like knowing the second you see someone, 'Oh this is going to be interesting. It's going to be dangerous, but look at me going in there anyway'," she told MTV News.

"I think that for me, it was the first time I ever kind of noticed that in myself.

"When you are curious about something you know might be bad for you but you know that you are going to go for it anyway because, if you don't, you'll have greater regrets about not seeing where that would go.

"I think for me it all went along with this record that was pushing boundaries, like the sound of this record pushes boundaries [and] it was writing about something I hadn't written before."

Swift continued: "My favorite thing [about the video] is that this girl not only gets sucked into this relationship with him but she loses who she was before and that's the saddest part of losing him, is that she can't remember who she was before she met him."

'I Knew You Were Trouble' - which is the second single from Swift's latest album Red - debuted its music video earlier in the month on the singer's 23rd birthday.